I have 2 ARs, one is a 20 inch a4 build with a heavy barrel, nothing fancy just a basic ar with a carry handle A2 stock and gas block.
The other is a more tricked out m&p15 with a 16in barrel, 15 in MI mlok handguard, primary arms 1-6, bcm stock, bcm bcg.

Fully loaded the a4 build weighs 9lbs and the m&p weighs 10lbs.
Im waiting on a suppressor and a light to come in and thats gonna add even more weight.

Is this a normal weight? What can i do to lower the weight?
Is dead air better than YHM? Do the different colors in fruit loops and apple jacks each have their own flavor? Is Garand Thumb really a thumb?

Shorter rails, lighter optics.

I like to keep it to under 6 pounds before accessories and I like lightweight accessories.

Curious, How can a 6.7 pound M&P15T plus 17oz optic and 10oz stock become a 10lb rifle? Which stock? Any other accessories. Heavy optic mount?

That seems abnormally heavy for what you have. Why does your m&p have a bcm bcg? What was wrong with the one that came in it?

Any recommendation's?

20" Heavy barrel gonna weigh a lot. Are you weighing with a full 30 round mag?

The cheaper way to go light is slick side upper, pencil barrels, maybe 2x LPVO, NO BUIS, Shorter barrels, light handguards.

More expensive is lighter BCG and titanium doodads. V7 Type Stuff

Swapped the bcg for a full auto bcm cuz everyone said they were better. I have the original semi auto bcg from s&w.
15 inch handguard from midwest industries with a MI low profile gas block
Magpul k2 grip.
BCM stock, not sure which one i forget, its got the wide cheek rest.
Magpul sling
Primary arms 1-6 and the free mount from them.
I use to have a red dot from sig on it, wanted to see farther and i wanted the ACSS reticle. It looks cool.

Rifle has a 16 inch heavy barrel, not sure exactly its whatever the m&ps come with.

No light on it yet, im waiting for an inforce light to come in and waiting for my dead air silencer to finish, all thats gonna add more

If what i have on now shouldnt weigh 10 lbs ill go get a new scale cuz i probably weigh less to

Yes im weighing with a full 30 round mag.

A basic 16” medium weight/gov profile barrel with typical 13” mlok rail comes in around 6.5lb. Can get closer to 6lb with careful choices. I like BCM’s rails and furniture, personally. Their barrels are okay. If tight grouping is a priority, Criterion barrels are a good  choice.

Plan on 1.5-2+Lb for an LPVO w/ mount…. So 7lb for a 16” carbine with optic is about as light as you should expect to get with well selected parts and a decent budget.

I dont care about getting 1 inch groups, but i dont want a 7 inch group either. The 20 inch barrel i chose to build it with a heavy barrel cuz of barrel whip and i was thinking a thinner barrel with a non free floated handguard was gonna be crap.

The m&p has its stock barrel, ive been thinking of returning it to its original state and building an upper with a gunner barrel from faxon, and either doing a lpvo with red dot or a red dot/magnifier.

Guessing your M&P is the heavy barrel variant. Change it out for a pencil barrel.

Your next opportunity is going to be the optic. Can you get by with a prism or red dot? I just dumped my LPVO for a PA 3X micro prism and I don’t find myself regretting it. Feels like an entirely different rifle and I already had an ultralight LPVO on it.

The best thing you can do to get a better handling 20” rifle is to trade it for a 16” rifle.

I have an obsession with the m16 so im gonna have a 20in. Im probably just gonna swap the barrel on it.

I dont mind swapping the lpvo out, anything specific i should look into? I have a red dot not mounted on anythimg right now but wanna see a little farther.

Leupold’s 3:1 LPVOs typically come in under 16oz. Their current version is the Mark 3, I believe. Their older VX-R versions are still a great scope if you can
Find one at a decent price. Great glass for the money, IMO.

I have a 20" AR (Faxon heavy fluted match bbl) that weighs 6lbs flat dry weight before optics.   I have an 18 that weighs a whisker over 5lbs dry weight (Faxon Gunner match).   Both will punch very respectable groups, and I am under $1k into each rifle.  It's very doable.

Quick suggested parts list for a first lightish weight build.

Anderson sport upper.
Any standard weight BCG that makes you happy.
Any charging handle you like
Faxon Gunner or Ballistic Advantage  pencil barrel (I'd buy whatever was on the best sale the day I was looking).
Aero Atlas S-One 10 in handguard (12 if you absolutely must).   (BCM MCMR or 2A Armament BL are also good choices).
Faxon .625 gas block, and any old A2 flash hider.  (You can save about 2 oz going with a thread protector, fyi)

That should come in around 3.25lbs, depending on  exactly which parts you picked.  

Any old mil spec ish complete lower with a lightweight (5 to 6 oz) stock and  3 oz buffer should come in around 2lbs.    For cheap lightweight stocks, AIMSports or Unbranded AR (and some others) sell a mil spec looking stock that has QD points near the front of it.   They come in about 5.7 to 6.1 oz after you remove the sling swivel.   JE Machine also makes a CAR stock knockoff that is around 4.5 oz if memory serves, but no QD.

Viola, 5.25 to 5.5lb AR, less than $650 if you caught a few things on sale.   Add a micro prism scope (PA, Burris, and Vortex all have good offerings around 8oz), a not too heavy light (3 to 4 oz), and a full pmag, and you'll be about 7lbs and not nose-heavy.    

As a rule of thumb, going lighter than that costs about 100 dollars per ounce you loose.    You can't really go lighter than about 4.75lbs dry weight without compromising something in terms of reliability or durability or both.

YMMV

I like the micro prisms. Stuff like the 3X Mini ACOG, Primary Arms 3X Microprism, or the Vortex 5X. I’d really recommend trying them first though, and avoid the standard weight ones entirely.

I have this on my carbine now and absolutely love it. Eye relief is a little tighter than my LPVO but it weighs 8 ounces and shoots great.
https://www.primaryarms.com/primary-arms-slx-3x-microprism-with-red-illuminated-acss-raptor-556-308-reticle-yard

Mostly I'd say go shorter if you dont need the velocity. There is weight and there is felt weight while shooting. The further out on the gun the more it feels heavy

Thinner and or shorter barrel.  Lighter handguard.

Carbon fiber barrel and rail.

sounds like barrel profile and length are the root cause

Smith and  Wesson should have equipped the M&P Sport with a pencil barrel from the start. The commercial profile barrel it comes with is silly.

Check out what Ian from Forgotten Weapons has done with his WWSD (what would Stoner do) project. Besides the poly lower/buttstock everything done can be used on most standard AR platform rifles.

Block 2 upper and razor 1-6

Is block 2 the quad rail?

I put a Ti barrel nut on the Midwest combat rail, a Ti gas block, then looked at both the Aero Precision mount and the wilson combat ultralight, went with the Aero ultimately. Really dropped the weight by a noticeable amount on a medium profile barrel.

But you won't have an issue with barrel whip with a shorter barrel. Shorter the stiffer. ((that's what my wife says)).

Sounds like a very specific type of role for that set up. I don't see a point in cutting down weight, but lighter barrel seems like the biggest way.

Pencil bbl (What an M&P Sport should have)

Troy SSC low profile M-Lok rail in 10.5" is only 6 ounces.

ACOG or T1

Balance > weight

If you're not shooting for precision groups (you've already admitted to that) then just put an A4 carry handle/rear sight on it and be done with it. Weight problem solved.

Honestly OP I run a slick rifle with plastic handguards to this day even after having run all the fancy stuff out there.  As a civilian now I don't have the need for all the gadgets so I run it slick and it runs goooooooooooooooooooooooooood..................all the extras won't help when it goes bad bro.

A2 Govt Profile on the 20”. Pencil on the 16”.

wow, 10lbs is... i don't know how you did that. that's my AR10's weight with a bigass scope on top.

some thoughts: if your rifle is front heavy, you'll feel the weight more. and, some of the heaviest parts of a rifle, i've found, tend to be in the front of the thing. so, get a lighter barrel (even a regular one will shave a lot of "felt" weight), and a light rail will do a lot too. but other than that, think about it. you have a BCG, a buffer, and everything else is pretty standardized. and a heavier buffer is oftentimes helpful.

so look at the barrel and rail, and obviously accessories. but, again, the "felt" weight (i made that phrase up, and it doesn't count for carrying the thing around on a sling, obviously) won't be so much if it's like, a heavier red dot near the ejection port. and even not counting the "felt" weight, it's usually accessories, barrel, and rail. maybe BCG.

so, yeah, look at the barrel and rail, and ditch any silly accessories you don't need, i'd think.

Thinner barrel profile.  Also, balance > overall weight

Man. That is heavy.  My primary carbine weighs 12.4 pounds  But that includes aimpoint T-2, magnifier, Dbal-D2, light, suppressor, loaded 40 round mag, and switches.  And that’s on an LWRC 10.3” gun which starts heavy. How is your S&W 10 pounds starting?

Get a light weight 14.5" barrel pin a muzzle brake, lighter mount and optic.

Pencil barrel. Try to get weight away from the muzzle end.

Don't count a loaded mag as part of the rifles weight

I tried a Google search without success, so does anyone know the weight of the stock MP 15 16" barrel?

I also have a M+P 15 with a MI 15" rail, Swampfox 1-10 with their mount, Mapul CTR stock and  grip, Olite weapon light. Weight as measured by a cheap bathroom scale with a loaded 30rd is just under 10lbs. Took multiple attempts to weigh and averaged due to quality of the scale. Whenever I start thinking it's too heavy, I remind myself to work the arms a little more lol.I am curious what the actual difference between the stock barrel and a lightweight pencil barrel might be.